Plated steel sheet having multilayer structure and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-10988845-B2
Application number	US-201716469980-A
Country	US
Kind code	B2
Filing date	Dec 21, 2017
Priority date	Dec 22, 2016
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

Provided is a plated steel sheet often used as materials for vehicles, home appliances, construction and the like and, more specifically, to a plated steel sheet having a multilayer structure and a method for manufacturing the same.

First claim

The invention claimed is:

1. A plating steel sheet having a multilayer structure, comprising:
a base steel sheet;
a first Zn layer formed on the base steel sheet;
a second Zn—Mg layer formed on the first Zn layer; and
a third Zn layer formed on the second Zn—Mg layer,
wherein the second Zn—Mg layer comprises: one or more of a Zn—Mg amorphous phase and a Zn—Mg alloy phase having a nanocrystalline form.

2. The plating steel sheet of claim 1 , wherein a content of Zn included in the Zn—Mg amorphous phase and the Zn—Mg alloy phase having a nanocrystalline form is 20 to 60 wt %.

3. The plating steel sheet of claim 1 , wherein a thickness of the first Zn layer is 1 to 3 μm.

4. The plating steel sheet of claim 1 , wherein a thickness of the second Zn—Mg layer is 0.5 to 1.5 μm.

5. The plating steel sheet of claim 1 , wherein a thickness of the third Zn layer is 1 to 3 μm.

6. A method of manufacturing a plating steel sheet having a multilayer structure, the method comprising:
preparing a base steel sheet;
forming a first Zn layer on the base steel sheet;
heating the base steel to a temperature of 50 to 120° C.,
vacuum-evaporating Mg on the first Zn layer to form a Mg-evaporated layer; and
vacuum-evaporating Zn on the Mg-evaporated layer in order for the Zn to be diffused into the Mg-evaporated layer to form one or more of a Zn—Mg amorphous phase and a Zn—Mg alloy phase having a nanocrystalline form.

7. The method of claim 6 , wherein the forming of the first Zn layer is performed by one of a hot-dip plating method, an electroplating method, and a vacuum evaporation method.

8. The method of claim 6 , wherein a degree of vacuum of a chamber during the vacuum evaporation of the second Mg layer and the third Zn layer is 1×10 −5 to 1×10 −2 mbar.

Assignees

• Posco

Inventors

• Ko Kyoung-Pil
• Nam Kyung-Hoon
• Kim Tae-Yeob
• Lee Dong-Yoeul
• Jung Yong-Hwa
• Jung Woo-Sung

Classifications

• C23C14/541

  Heating or cooling of the substrates · CPC title

• C23C14/16 Primary

  on metallic substrates or on substrates of boron or silicon · CPC title

• C23C14/025

  Metallic sublayers · CPC title

• C23C2/28

  Thermal after-treatment, e.g. treatment in oil bath · CPC title

• C23C2/26

  After-treatment (C23C2/14 takes precedence) · CPC title